Dodge Ram Truck 1500-2500-3500. Manual — part 421

FCM-RIGHT STOP LAMP OUTPUT CIRCUIT LOW (CONTINUED)

2.

RIGHT BRAKE LAMP FEED CIRCUIT SHORT TO GROUND

Turn the ignition off.

Disconnect the IPM C4 harness connector.

Measure the resistance between ground and the Right Brake Lamp
Feed circuit.

Is the resistance below 5.0 ohms?

Yes

>> Go To 3

No

>> Repair the Right Brake Lamp Feed circuit for a short to

ground.

Perform BODY VERIFICATION TEST - VER 1.

3.

FRONT CONTROL MODULE

Turn the ignition off

Disconnect the FCM connector.

Disconnect the IPM C4 harness connector.

Measure the resistance between ground and the Right Brake Lamp Feed circuit in the IPM.

Is the resistance below 5.0 ohms?

Yes

>> Replace the Power Distribution Center(PDC).

Perform BODY VERIFICATION TEST - VER 1.

No

>> Replace the Front Control Module.

Perform BODY VERIFICATION TEST - VER 1.

8L - 90

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

DR/DH

FCM-RIGHT STOP LAMP OUTPUT CIRCUIT OPEN

DR/DH

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

8L - 91

FCM-RIGHT STOP LAMP OUTPUT CIRCUIT OPEN (CONTINUED)

For the Exterior Lighting system circuit diagram (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERIOR -
SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition on

•

Set Condition:
The FCM detects an open condition

Possible Causes

RIGHT BRAKE LAMP FEED CIRCUIT OPEN

POWER DISTRIBUTION CENTER

FRONT CONTROL MODULE

1.

INTERMITTENT CONDITION

Turn the ignition on.

With the DRBIII

T

, clear all FCM DTC’s.

Actuate the Stop Lamps.

With the DRBIII

T

, read the DTC information.

Does the DRBIII

T

read: Right Stop Lamp Output

Circuit Open?

Yes

>> Go To 2

No

>> The condition that caused the symptom is

currently not present. Inspect the related
wiring for a possible intermittent condition.
Look for any chafed, pierced, pinched, or
partially broken wires.

Perform BODY VERIFICATION TEST -
VER 1.

8L - 92

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

DR/DH

FCM-RIGHT STOP LAMP OUTPUT CIRCUIT OPEN (CONTINUED)

2.

RIGHT BRAKE LAMP FEED CIRCUIT OPEN

Turn the ignition off.

Disconnect the IPM C4 harness connector

Measure the resistance of the Right Brake Lamp Feed circuit.

Is the resistance above 5.0 ohms?

Yes

>> Repair the Right Brake Lamp Feed circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

No

>> Go To 3

3.

FRONT CONTROL MODULE

Turn the ignition off

Disconnect the FCM from the IPM.

Disconnect the IPM C4 harness connector.

Measure the resistance of the Right Brake Lamp Feed circuit.

Is the resistance above 5.0 ohms?

Yes

>> Replace the Power Distribution Center.

Perform BODY VERIFICATION TEST - VER 1.

No

>> Replace the Front Control Module.

Perform BODY VERIFICATION TEST - VER 1.

DR/DH

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

8L - 93